Policy Implications and Future Research

The two systematic reviews in this thesis reveal the association between childhood maltreatment and epigenetics and the development of depression and/or anxiety. They reinforce the importance of life course strategies for prevention and the need for effective programs and policies to reduce the occurrence of mental illnesses. Pregnancy and early life experience and environment, which may lead to epigenetic changes, play an essential role in lifetime mental wellbeing. Decreasing the amount of maltreatment and other adverse experience in childhood and during pregnancy should be the target for mental illness prevention and mental health promotion.

This thesis also indicates that current child and adolescent mental health services effectively improved most clients’ functioning. Severity of mental problems can affect the effectiveness of treatment. Shortening the length of each treatment cycle may improve the efficiency of resource use but at the expense of clients that need more time to achieve a more optimal functional improvement. Personalized treatment services are required to meet clients’ specific needs and maximize the cost effectiveness of services.

Given the current controversies regarding the use of stimulant medications in children, this thesis indicates that stimulant use in children and adolescents appears to be protective against the future development of bipolar disorder. However, the severity of the initial disease itself and comorbidity serve as an indicator of the development of future disease.

From a research perspective future epidemiological studies should be more linked to epigenetics and adopt longitudinal study designs to trace the change overtime. To allow for a systematic comparison of studies, an agreed upon consistent set of standards involving a minimum set for items for the execution and reporting of epigenetic studies is warranted.

7.3 Conclusion

1) Early childhood maltreatment is a significant causal factor in the development of future depression and anxiety, and that the incidence of depression and anxiety could be

significantly reduced by reducing the prevalence of various types of childhood mal treatment. 2) Alterations in gene expression (epigenetic events) can lead to increased risk of depression.

Such epigenetic events can be the result of in utero exposure of fetus to a variety of negative stressors.

3) Early treatment of mental health problems in children and adolescents is beneficial in

increasing their positive functioning in and across life domains. Early intervention is likely to change the trajectory of disease progression.

4) Stimulant medication used to treat children and adolescents for ADHD does not have negative (iatrogenic) effects leading to an increased risk of developing BPAD.

The clear public health message is that early reduction in risk factor exposure in utero and in childhood and adolescence and the early treatment of mental health problems has a very positive effect in reducing the onset and further development of psychiatric disease and mental health problems.

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